FAW Driver Seat Assembly: The 6-Part Secret to All-Day Driving Comfort

Welcome to this critical ergonomic and safety analysis of the FAW Driver Seat Assembly (Assembly 695). This is the complete, 6-component-type, “Air-Ride” (air suspension) and “Heated” (electric heat) driver’s seat for the FAW Jiefang CA4251P66K24T1A3E5 6×4 diesel semi-trailer tractor. This is arguably the single most important “logic” assembly for driver health, safety, and long-haul comfort.

The FAW Driver Seat Assembly (P/N 6800010BD04-C00) is a sophisticated, “dual-logic” system. Its first “logic” is “Air Suspension,” using a dedicated ‘Air horn assy’ (3506805-91W) and ‘Air tube assy’ (6800020AA01) to “float” the driver, isolating them from the truck’s chassis vibration. Its second “logic” is “Electric Heat,” (as noted in the title), providing critical comfort and reducing muscle fatigue in cold-weather operation.

This in-depth guide is essential for fleet managers and technicians. We will deconstruct the entire FAW Driver Seat Assembly into its 6 distinct Minimum Serviceable Unit (MSU) types. We will analyze the “structural” logic of the main ‘Seat Assy’ (MSU 1), the “pneumatic” (air-ride) logic of the ‘Air Tube’ and ‘Air Horn’ (MSUs 2 & 3), and the critical “anti-vibration” fastener logic (MSUs 4, 5, 6) that secures the driver to the cab.

MSU 1: The “Dual-Logic” Core – ‘Driver Seat Assy’ (6800010BD04-C00) (The “Longer” Module)

The ‘Driver seat assy’ is the primary component and MSU 1. This is the “black box” of the FAW Driver Seat Assembly. It is a “logic” assembly that is replaced as a single unit. It combines a structural frame, ergonomic foam, a durable cover, and its two “active” logic systems: Air Suspension and Electric Heat.

1. The “Air-Ride” Suspension Logic:

This is the core “health and safety” logic. A truck’s chassis is subjected to constant, high-frequency “road buzz” and low-frequency “bouncing.” This “logic” of the ‘Air-Ride’ seat is to *isolate* the driver’s spine from this vibration.

The FAW Driver Seat Assembly contains an integrated “air spring” (a rubber airbag) and a height-adjustment valve. This valve (fed by MSU 2 & 3) allows the driver to add or remove air, “tuning” the seat to their exact weight. This “floats” the driver, absorbing up to 90% of the harmful vibrations that lead to chronic back pain and driver fatigue.

2. The “Electric Heat” Logic:

As the title notes, this is an “electric heated” seat. This “logic” is for both comfort and health. Buried beneath the seat’s upholstery are “resistive heating elements” (wires).

In cold-weather operation, the driver can activate this system, which provides “logic”-controlled, therapeutic warmth to the seat cushion and lumbar (lower back) area. This “logic” is critical for preventing muscle stiffness and back strain during long, cold hauls.

3. The “Ergonomic & Safety” Logic:

The FAW Driver Seat Assembly is the “HMI” for the driver’s body. Its “logic” is “adjustability.” The seat features multiple controls for:

• Lumbar Support: An adjustable (often pneumatic) cushion that presses into the driver’s lower back to maintain a healthy posture.
• Fore/Aft & Rake: Slides and backrest angle, allowing the driver to achieve the perfect, safe distance from the steering wheel and pedals.
• Side Bolsters: “Wings” on the cushion and backrest that “logic” is to hold the driver securely in place during sharp turns.

Serviceability (MSU): The ‘Driver seat assy’ is the primary MSU. It is a sealed unit. If the air-ride valve fails, the heater element burns out, or the internal frame cracks, the *entire* assembly (6800010BD04-C00) is unbolted (via MSUs 4, 5, 6) and replaced.

Core 2: The “Pneumatic Supply” Logic (MSUs 2 & 3)

This group of MSUs is the “lifeblood” of the air-ride system. This is the “logic” that feeds the FAW Driver Seat Assembly with high-pressure air from the truck’s main pneumatic system.

MSU 2: ‘Air tube-multiway joint to air horn’ (3506805-91W)

MSU 3: ‘Air outlet tube-driver seat’ (6800020AA01)

These two MSUs form the complete “plumbing” from the chassis to the seat. The “logic” is as follows:

• “Supply Logic” (MSU 2): This tube “taps” into the truck’s main air system (at a “multiway joint”) and delivers that air to the ‘Air Horn’. The “Air Horn” (气喇叭) in this context is a “logic” mistranslation; it is the *valve* or *regulator* for the seat.
• “Delivery Logic” (MSU 3): This is the final “pigtail” that connects the regulator *to* the air-intake port on the ‘Driver Seat Assy’ (MSU 1).

These are critical MSUs. The tubing is made from high-pressure, oil-resistant nylon. The #1 failure “logic” is chafing. If not routed correctly, these tubes can “chafe” against the cab’s metal floor, creating a pinhole leak. This results in a “hissing” sound, a “dead” seat that won’t inflate, and a dangerous air-loss from the main brake system.

Core 3: The “Anti-Vibration” Fastener Logic (MSUs 4, 5, 6)

This final group of MSUs is the “logic” that secures the FAW Driver Seat Assembly to the cab floor. This is a safety-critical, 18-piece (6+6+6) system.

MSU 5 & 6: ‘Air tube clamp-driver seat’ (6800016AA01) & ‘Hexagon nut’ (CQ34005) – Qty 6 (each)

This is the “anti-chafe” logic. The six ‘Clamps’ are used to securely fasten the ‘Air Tube’ (MSU 3) to the seat’s sub-frame and the cab floor. The six ‘Nuts’ secure these clamps. This “logic” is critical to prevent the chafing and air leaks described above.

MSU 4: ‘Combination bolt’ (CQ1460825F6) – Qty 6

This is the “structural logic.” These six (6) heavy-duty bolts are what secure the ‘Driver Seat Assy’ (MSU 1) *to the cab floor*.

The “Combination” (组合) logic is the key. These are not standard bolts. They are MSUs with a *captive, pre-attached lock washer* (e.g., a serrated or spring washer).

A driver’s seat is under constant vibration and shear-force (from acceleration/braking). A standard bolt *would* vibrate loose. The “lock washer” on this bolt “bites” into the seat’s metal frame, providing constant tension. This “anti-vibration” logic is a critical safety feature that ensures the driver’s seat *cannot* detach from the cab floor in a collision.

FAW Driver Seat Assembly Parts List & Specifications

The following table provides the complete, detailed breakdown of all 6 component types identified in the FAW Driver Seat Assembly (Electric Heated) for the FAW CA4251P66K24T1A3E5 tractor.

Specifications

The specifications for the FAW Driver Seat Assembly are defined by its function as a “dual-logic” (Air-Ride + Electric Heat) ergonomic safety system.